The Belgium international hasn't settled into life at White Hart Lane too well and would like a move after just one season in order to secure Champions League football next season.
Napoli will be able to offer that to the 26 year-old with the side set to clinch third place in Serie A ahead of Fiorentina and Vertonghen would be all but guaranteed a starting spot with the area a real weak spot in the San Paolo side at the moment.
It is believed that Napoli would offer Switzerland international Valon Behrami in a straight swap deal but the Spurs would probably demand something more than just Behrami if they were interested at all in the former West Ham man who had a horrible time while in EPL the first time around.
Vertonghen has made 23 appearances in the English Premier League which is a very similar amount to the 20 appearances which 28 year-old Behrami has made in Serie A.